Ineffective management of blood glucose (BG) levels during preconception and pregnancy has been associated with severe maternal and fetal complications. Apart from the physical and psychological burden of these complications on patients, healthcare costs related to managing these issues are substantial. Preconception care emphasizing stringent glycemic control in the preconception period and continued through early pregnancy can dramatically reduce these risks. However, the use of preconception care in the US has been disappointingly low due to a variety of organizational, provider, and patient centered factors. Furthermore, efforts to achieve tight glycemic control can increase the risk of severe hypoglycemia (SH) in T1DM women, potentially leading to serious health consequences (e.g., traffic accidents, maternal death). This may also impede patients' progress to achieve their glycemic targets for pregnancy. Aforementioned reasons together make BG management even more challenging for this patient population compared to others with diabetes. There is a vital need to equip this critical population of TIDM women contemplating pregnancy with practical self-management skills that they can actively use to better understand and manage their BG levels, and achieve their target glycemic control without undue risk of hypoglycemia. BGATHome is an automated, tailored, Internet version of Blood Glucose Awareness Training (BGAT), a face- to-face, psycho-educational intervention for T1DM patients developed by our research team. The program has demonstrated effectiveness in terms of improving glycemic control, reducing extreme BG levels, SH, diabetic ketoacidosis, and improving patients' psychological functioning. Historically, in our BGAT-related studies, we have excluded T1DM women who were either contemplating pregnancy or were pregnant during the course of our studies given their unique diabetes-related clinical needs. In this project, we will develop and test a specialized version of BGATHome for use with T1DM women who are contemplating pregnancy to examine its efficacy as an intervention for these women to better regulate their BG levels and to meet their diabetes-related clinical targets for conception. Using formative research with the targeted patients, their significant others, and providers, we will determine and create a new version of BGATHome tailored for this population. This new intervention, BGAT-Pregnancy, will then be tested in a RCT involving T1DM women contemplating pregnancy to examine feasibility and preliminary efficacy. Interviews with trial participants, their significant others, and potential providers will be conducted to enable further optimization of the intervention in preparation for a subsequent R01 submission. This will be the first study investigating the use of the Internet to improve detection and management of extreme BG levels in T1DM women contemplating pregnancy. If proven efficacious, BGATHome for Pregnancy would provide a crucial supplement to preconception care for the US T1DM women, substantially reducing dangerous complications, and improving psychological outcomes.